Author

Date of Award

Document Type

Degree Name

Administrative Home Department

School of Forest Resources and Environmental Science

Advisor 1

Rod Chimner

Advisor 2

Erik Lilleskov

Committee Member 1

Judith Perlinger

Abstract

Although knowledge of peatland CH4 and CO2 exchange in temperate mountain ecosystems is available, information about carbon (C) exchange in peatlands of the Andean mountains is limited and these ecosystems may behave differently given the particular characteristics of the Andean tropics. These ecosystems are highly productive and under pressure by grazing. Our first objective was to measure baseline carbon dioxide (CO2) and methane (CH4) flux in an undisturbed peatland in Cayambe-Coca National Park. Our second objective was to quantify CO2 and CH4 fluxes in an intensively cattle grazed peatland near Antisana Ecological Reserve. CO2 and CH4 effluxes were measured using a static chamber method. The mean NEE values for the undisturbed and disturbed site were -0.69 ± 0.08 and -1.25 ± 0.13 g CO2 m-2 hr-1 respectively. A significant correlation between microtopography and CO2 and CH4 flux was found in the undisturbed site, with higher NEE, GPP, ER and CH4 values in hummocks than in lawns. Microtopography doesn’t seem to be a controller of CO2 efflux in the grazed site, although the NEE and GPP rates are higher than those found in the undisturbed site, and show a linear relationship with vegetation cover. CH4 emissions in the undisturbed site were low (8.1 ± 1.17 mgCH4 m-2 d-1). However, CH4 emissions at the grazed site were very high (132.25 ± 34.22 mg CH4 m-2 d-1), which might be attributed to the high physical impact and inputs from cattle. In summary, it appears that cattle grazing may be capable of large changes to C exchange and greenhouse gas fluxes in Andean peatlands.